Systemic fungal infections caused by Candida species, Cryptococcus neoformans, Histoplasma capsulatum and the like are often serious or fatal. There continues to be a need for an antifungal agent which is effective and at the same time non-toxic to the patient being treated. A number of known antifungal agents while effective in eliminating the disease are of limited usefulness because of toxic or other undesirable side reactions. In many cases the toxicity is related to the amount of the drug and could be eliminated or reduced if a lesser amount of the drug could be employed. Thus, it would be desirable if a combination could be found which is synergistic or which has a second component that has a potentiating effect on the known antifungal agent thereby reducing the amount of drug required with concomitant reduction or elimination of side reactions.
There are reports in the literature that by administering amphotericin with other antibiotics, Candida albicans is sensitized to antifungal agents. Thus, for example, minocycline and amphotericin B have been found to be a synergistic composition against Candida albicans, Leev et al, Brit. J. Infect. Dis., 136, 263-270 (1977). However, combinations with amphotericin is not satisfactory because of the toxicity of amphotericin to human beings.